Split bta_dm_discover into bta_dm_discover_services and bta_dm_discover_name

When searching for devices, BT stack had capability to search for
specific service. That meant connecting to every classic address in inquiry
database, performing SDP and returning results that expose particular
service.

This functionality is never used, "services" parameter to search request
was deleted in Change-Id: I85ce622d9e99ec4430032d0233d588b2ec5a9cdf

The code for performing name and service discovery on each inquiry result is
now in bta_dm_discover. Part responsible for service discovery is also
used after bonding, to discover LE and Classic profiles.

This patch splits name and service discovery into separate functions, as
they are never peformed together. Wether name or service discovery is
performed, is decided based on tBTA_DM_SEARCH_CB.services, which is
removed in next patch.

Bug: 330675788
Flag: exempt, trivial
Test: mma -j32
Change-Id: Ib1dd3ce94e95f49f75da946c152773f78711604d